What was found
ON APPROACH, AT ABOUT 10K FT, BOTH PILOTS DETECTED SIGNIFICANT ODOR OF DIRTY SOCKS OR SOUR MILK. SUSPECTING POSSIBLE PACK FUME EVENT, WE TURNED OFF PACK 1 TO ISOLATE AND ODOR INSTANTLY WENT AWAY. TROUBLESHOT IAW TSM 05-50-00-810-831A. IAW DECISION TABLE, ODOR ISOLATED TO ENG NR 1. PERFORMED GVI OF ENG NR 1 FOR LEAKS. FOUND RESIDUAL OIL AND HYDRAULIC FLUID FROM PREVIOUS LEAKS. CLEANED AS NECESSARY. PERFORMED IDLE LEAK CHECKS IAW AMM 71-00-00. NO LEAKS NOTED AT THIS TIME AND NO ODOR IN CABIN AT THIS TIME.